Mercury, cadmium, lead and arsenic levels in three pelagic fish species from the Atlantic Ocean: intra- and inter-specific variability and human health risks for consumption

Cadmium Accumulation and Kinetics in Solea senegalensis Tissues under Dietary and Water Exposure and the Link to Human Health

Bioaccumulation of cadmium was assessed in different tissues of the benthic fish Solea senegalensis. Juvenile Senegalese soles were simultaneously exposed to cadmium-contaminated diet (Hediste diversicolor) and water during 14 days and allowed to depurate for another 14 days. Cadmium content was measured in muscle, gills, liver and intestine, with recorded values increasing in these tissues in this same order. Muscle showed a considerably lower cadmium accumulation after 14 days of uptake. Cadmium kinetics in juvenile Senegalese soles revealed that the highest uptake flux of this metal occurred in the intestine. Cadmium depuration from the liver was not detected, which suggests the existence of a storage compartment for this metal in Solea senegalensis during uptake and depuration. Comparisons between maximum acceptable values for cadmium in the muscle, the Target Hazard Quotient and the Estimated Weekly Intake, indicated that acceptable limits were not exceeded, and the muscle of juvenile Senegalese soles could be considered safe for human consumption.

A survey of arsenic, mercury, cadmium, and lead residues in seafood (fish, crustaceans, and cephalopods) from the south-eastern Mediterranean Sea

Seafood is capable of bioaccumulating heavy metals (HM), making it a potentially major dietary source of HM for humans. Presently, little data exists on seafood from the eastern-most boundary of the Mediterranean Sea. This study aims to provide exposure insight of the Israeli population to HM through the consumption of locally caught seafood by assessing the levels of arsenic, mercury, cadmium, and lead in raw tissues of seafood. A wide survey of local fisheries was conducted providing 296 samples from 11 different species, including seven fish, two crustacean, and two cephalopod species. Total arsenic, cadmium, and lead were analyzed by graphite-furnace atomic absorption. Total mercury was measured by cold-vapor mercury analyzer. Arsenic speciation was performed by anion chromatography-inductively coupled plasma sector field mass spectrometry. Results suggested that the total arsenic concentrations were significantly higher in crustaceans and cephalopods than fish. Arsenic speciation revealed two samples that exceed 1 mg/kg of inorganic arsenic, whereas methylated arsenic was below the detection limit. Elevated mercury levels were detected in the commercial benthic species Mullus barbatus (red mullet), cadmium was detected in one-third of the samples, and lead detected in eight samples. Comparing the results to health guidelines, 99.4% of seafood tested in this study abide with acceptable levels of heavy metals in seafood, as defined by both Israeli and European Union guidelines.

Mercury, Lead, and Cadmium in the Muscles of Five Fish Species from the Mechraâ-Hammadi Dam in Morocco and Health Risks for Their Consumers

This study aims to assess the degree of metal contamination (mercury (Hg), cadmium (Cd), and lead (Pb)) in the muscles of five species of fish Esox lucius, Sander lucioperca, Micropterus salmoides, Lepomis macrochirus, and Scardinius erythrophthalmus, from the Mechraâ-Hammadi Dam between July 2017 and May 2018, and to conduct a risk assessment for human consumers. Trace metals were determined by Graphite Furnace Atomic Absorption Spectrometry for the Pb and the Cd and by Cold Vapor Atomic Absorption Spectrometry for the Hg. The results gotten from the study of the muscles of the different fish species show that the higher mean amounts of Cd and Hg were determined in E. lucius, and the maximum mean levels of Pb were detected in S. erythrophthalmus. Results suggested that demersal fishes inhabiting near the sediments and piscivorous fishes with higher trophic level were likely to accumulate higher trace metal concentrations. The general order of bioaccumulation of the trace metals measured in the muscles of the fish species is as follows: Hg > Pb > Cd. Therefore, the bioaccumulation of Hg in fish studied is more important than that of Cd and Pb. Furthermore, these concentrations are higher in summer than in winter for all trace metals. All the values of the trace metals in the muscle tissues are below the maximum limits recommended by the European Community (EC) N° 1881/2006. However, estimation of noncarcinogenic health risks by the target hazard quotient indicated no obvious noncarcinogenic risks to humans that consume those fishes (THQ < 1). Results of THQ and maximum safe consumption indicated that Hg may cause more harm to human by fish consumption especially for E. lucius and S. lucioperca. Therefore, reduced intake of carnivorous fishes should be promoted as part of a healthier diet.

Nutritional value and bioaccumulation of heavy metals in muscle tissues of five commercially important marine fish species from the Red Sea

The study evaluated the nutritional quality and investigated the heavy metals concentration in muscle tissues of five commercially important marine fish species, including brownspotted grouper (Epinephelus chlorostigma), squaretail coralgrouper (Plectropomus areolatus), black pomfret (Parastromateus niger), goldbanded jobfish (Pristipomoides multidens), and blueskin seabream (Polysteganus coeruleopunctatus) from the Red Sea, Jeddah Coast, Saudi Arabia. Significant differences (p < 0.05) were observed in the proximate chemical composition of fish muscles in these species. The highest protein content (17.66 ± 0.58%) was achieved in blueskin seabream while the lowest (15.28 ± 0.46%) was observed in brownspotted grouper. The highest lipid content (2.97 ± 0.45%) was recorded in squaretail coralgrouper while the lowest (1.52 ± 0.26%) was observed in blueskin seabream. Heavy metal concentrations varied significantly within and between fish species under study (p < 0.05). Significant differences in the concentration of heavy metals among fish species were recorded. Results revealed that the bioaccumulation of Cr, Fe, Ni, and Cd in muscles of fish species under study was higher than the standard concentration, but that of Mn, Cu, and Pb were less than the standard concentration recommended in the EU, FAO, and WHO guidelines. In conclusion, these fish species represent a high-quality food source but is unsafe due to the level of certain minerals in their tissues. Results also indicated that the Red Sea environment is contaminated with heavy metals, which was reflected in the tissues of fishes used in this study.

Mercury and selenium in fish from the eastern part of the Adriatic Sea: A risk-benefit assessment in vulnerable population groups

The study examines the levels of total mercury (Hg) and selenium (Se) in the muscle tissue of 12 commercially important fish species (n = 717) from 48 locations in the eastern Adriatic Sea, as a function of fish species, size and habitat. Risks and benefits of fish consumption regarding Hg and Se in children (7 years) and women of reproductive age (30 years) were also evaluated. All samples but one were compliant with the European regulatory limit for Hg in fish muscle. Concentrations (μg g^-1 ww) of Hg (range: 0.014-1.37) and Se (range: 0.184-1.12) and Se:Hg molar ratios in fish were associated with habitat type. Demersal species had the highest Hg and the lowest Se concentrations, while pelagic species had the lowest Hg concentrations, highest Se concentrations and Se:Hg molar ratios. All species had Se:Hg molar ratios above 1 (range: 1.4-66.9) and a selenium health benefit value (HBV_Se) above zero (range: 3.3-9.3), indicating Se excess after Hg sequestration. The intake of two meals per week of small pelagic-neritic and bento-pelagic fish is estimated to be a valuable source of essential Se, and does not pose a risk from toxic Hg exposure in children and women during the vulnerable reproductive period. Due to the low Hg and favorable Se:Hg molar ratio and HBV_Se index, small pelagic species offer a good risk to benefit ratio of fish consumption and could be considered an optimal choice in these sensitive subpopulations.

Seasonal and ontogenic variations of metal content in the European pilchard (Sardina pilchardus) in northwestern African waters

Marine fishes are exposed to great human-induced alterations due to the indiscriminate discharges into the sea, increasing marine pollution. For this study, 324 specimens of Sardina pilchardus from the Canary Islands were analized during a period of 2 years (June 2016 to May 2018). The concentration of 11 metals and trace elements (Al, B, Cd, Cr, Cu, Fe, Li, Ni, Pb, V and Zn) was determined in each individual using the Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES) technique. Statistical analyses were carried out considering the following factors: oceanographic season, maturity of the gonads in the seasons, size of the specimens. Sardina pilchardus specimens captured in the hot season presented higher Ni, Li and Pb levels than the specimens caught in the cold season. Immature specimens had higher concentration in more metals than the mature specimens. This fact may be due to the fact that these specimens require a much higher metabolic rate due to their growth and do not detoxify like mature specimens. Significant differences were found in the concentration of metals in all the analyzes performed.

Polycyclic aromatic hydrocarbons in wild and farmed whitemouth croaker and meagre from different Atlantic Ocean fishing areas: Concentrations and human health risk assessment

This work assessed the concentrations of 18 polycyclic aromatic hydrocarbons (PAHs) in edible tissues of whitemouth croaker (Micropogonias furnieri) and meagre (Argyrosomus regius) captured in different Atlantic Ocean fishing areas and available to Brazilian and Portuguese consumers. Total PAH (∑PAHs) levels ranged from 1.32 to 5.41 μg/kg ww in wild-caught croaker and 2.66 (wild)-18.0 (farmed) μg/kg ww in meagre. Compounds with 2- and 3-rings represented 54-86% of ∑PAHs in the muscle tissues of wild-caught species (croaker and meagre) being naphthalene, fluorene, and phenanthrene the predominant compounds. ∑PAHs in farmed meagre were 4-7 times higher than in wild-caught meagre, with 2-, 3-, 4-, 5-, and 6-ring compounds representing 15, 18, 44, 22, and 1% of ∑PAHs, respectively. Benzo(a)pyrene levels in farmed meagre varied between 0.06 and 0.34 μg/kg ww. Crude oil refining and combustion sources were identified as the major sources of PAHs in FAO 27, 34 and 41 Atlantic Ocean fishing areas. The biometric characteristics (length, weight, moisture, and fat content) and ∑PAHs allowed to discriminate between wild-caught and farmed meagre samples and between meagre and croaker. Assessment of carcinogenic risks suggested that a diet exclusive on farmed meagre may pose additional risks for the health of European top consumers fish.

Assessment of environmental health based on a complementary approach using metal quantification, oxidative stress and trophic ecology of two gull species (Larus michahellis & Larus audouinii) breeding in sympatry

Metal pollution is currently a major issue in marine ecosystems, as organisms, and particularly seabirds, are exposed and accumulating increased levels from several anthropogenic sources. A set of 13 metals were quantified in two gull species breeding in sympatry, and in two distinct colonies separated by ca. 400 km. Oxidative stress was measured, and stable isotope analyses were used to link metal contamination and oxidative stress with the trophic ecology of each species/population. There was a clear segregation of metal contamination between the two species and to a much lesser extent between colonies. Overall, Audouin's gull was the most contaminated species for most metals, once this species relies mainly on fish and other marine resources. The Yellow-legged gull feeds regularly on terrestrial food sources besides fish, which may dilute contamination levels. Oxidative stress responses were related with birds' trophic ecology and foraging habitat, but apparently not with metal contamination.

Accumulation of trace elements in selected fish and shellfish species from the largest natural carp fish breeding basin in Asia: a probabilistic human health risk implication

Intake of fish contaminated with non-essential hazardous trace elements poses a significant risk to human health. In this study, trace elements (As, Pb, Cd, Cu, Ni, and Zn) were measured in edible tissues of seven commercially important fish and shellfish species (Otolithoides pama, Pseudapocryptes elongatus, Macrobrachium rosenbergii, Liza parse, Notropis atherinoides, Apocryptes bato, and Rhinomugil corsula) from a natural carp breeding basin, Halda river, Bangladesh. The elements were detected by inductively coupled plasma-mass spectrometry (ICP-MS), and the hierarchy of elemental levels (mg/kg) was Zn (61.56) > Pb (30.45) > Ni (26.81) > Cu (21.09) > As (1.49) > Cd (0.24). Among the analyzed elements, Pb, Ni, and Zn for some fish species exceeded the permissible dietary limit, suggested by national and international agencies. In addition, results of bioaccumulation factor (BAF) indicated that most of the studied species were bioaccumulative in nature (BAFs > 1000), and the mean BAF of elements were found in the following order: Zn (3156.74) > Ni (1629.30) > Cu (1566.77) > As (997.14) > Pb (259.98) > Cd (216.52). However, the species, L. parse being omnivorous represented the highest BAF (stored higher concentrations of metals) as compared to other species. The growth pattern of all the species was negatively allometric, and the health condition of the species varied from poor to good state revealed from the estimated Fulton's condition factor (FC). For the evaluation of health hazards, estimated weekly (EWI), target hazard quotient (THQ), and carcinogenic risk (CR) were calculated for both adults and children. Results of EWI showed As, Pb, and Ni surpassed provisional tolerable weekly intake (PTWI)-recommended guidelines. The non-carcinogenic health effect (TTHQ) might not appear for both types of consumers (as TTHQ < 1), and CRs of all consumers were also in acceptable range (10^-6 to 10^-4). However, the probabilistic distribution through Monte Carlo simulation revealed that children were more vulnerable to non-carcinogenic (67.3%) and carcinogenic risk effect (47.3%) for Pb. Meanwhile, adults obtained the probability of 0.7% and 36% for THQ and CR effect, respectively, interpreting less vulnerable.

Metallic Contamination of the Muscles of Three Fish Species from the Moulouya River (Lower Moulouya, Eastern Morocco)

This study introduces a spatiotemporal evaluation of the metallic contamination with three trace metals (mercury, lead, and cadmium) in the muscles of three fish species (Lepomis macrochirus, Barbus callensis, and Barbus nasus), of which the samples were taken from three stations in the Moulouya River: the confluence of the Moulouya River and the Sebra River (station 1), the neighbourhood of the farms in the region of Aklim downstream from confluence of Lakhmis river (station 2), and the level of ancient bridge of Ras El Ma-Moulouya (station 3), during the period from July 2017 to May 2018. The results have allowed us to highlight rather high contents of lead and mercury in the fish muscles, mainly in station 1, which receives domestic and industrial discharges. The contents of cadmium in all fish species in different stations are very low. Moreover, all concentrations assessed in different fish species do not exceed the maximum limit recommended by European Community (EC) Commission Regulation No. 1881/2006.

Fish-Based Baby Food Concern-From Species Authentication to Exposure Risk Assessment

In this work, two different but complementary approaches were used to evaluate the reliability of fish-based baby foods as a source of safe nourishment for babies. More specifically, barcoding analysis based on the Cytochrome Oxidase I sequences was used for fish species authentication and an analysis of metal/metalloid levels was performed to estimate the exposure risk assessment derived from consumption of selected fish-based baby food in infants and toddlers. COI DNA barcoding revealed that in three samples the species detected did not match the common name of the species shown on the label. In particular, G. chalcogrammus and M. australis were found in place of M. merluccius and O. mykiss was found in place of S. salar. The analysis of exposure risk assessment indicated a low risk for developing chronic systemic and carcinogenic effects in infants and toddler, under an exposure scenario based on daily consumption of a single box of fish-based baby food. However, it is important to highlight that in order to provide a comprehensive risk assessment it would be important to supplement the levels of exposure resulting from the total diet. Overall, our results suggest that more attention should be paid by authorities to ensure the safety of food for infants and toddlers.

Use of biochemical markers to quantify the toxicological effects of metals on the fish Sciades herzbergii: potential use to assess the environmental status of Amazon estuaries

Enzymatic biomarkers, especially oxidative-stress enzymes, are useful for assessing the status of aquatic environments. The present study used biochemical markers determined in nervous, gill, and liver tissues of Sciades herzbergii, concomitantly with analyses of trace metals in the tissues and bottom sediment, to evaluate environmental quality in Amazon estuaries. The study was conducted from March 2014 to February 2016 in two areas: Caeté estuary in Bragança, state of Pará, which is relatively unimpacted; and São Marcos Bay, next to a harbor in São Luís, state of Maranhão. In the laboratory, the fish were weighed (g) and measured (cm). Fragments of the gills, the brain, and the liver were biochemically analyzed, and the metal contents in the brain, the liver, and the muscle tissues were determined. Turbidity was significantly higher (p < 0.05) in São Marcos than in Bragança. Specimens of S. herzbergii were smaller in São Marcos, and aluminum, iron, nickel, copper, cadmium, and mercury levels were higher in bottom sediment (p < 0.05) collected at this location. Fish from São Marcos contained significantly higher (p < 0.05) concentrations of aluminum, iron, and cadmium in the muscle tissue than fish from Bragança. In addition, fish from São Marcos had significantly higher concentrations of nickel in both the nervous and hepatic tissues. Only fish from São Marcos contained measurable concentrations of mercury in the liver and muscle. Fish from Bragança had copper concentrations in the liver significantly different from those captured at São Marcos (p < 0.05). The activities of gill glutathione S-transferases (GSTs) (F = 6.62; df = 1, 16; p < 0.05) and liver CAT (F = 10.22; df = 1, 16; p < 0.05) were higher in fish from São Marcos. However, ChE in brain tissues and lipid peroxidation (LPO) in the gills and liver did not differ significantly between fish from both areas. The physico-chemical conditions of the water and the concentrations of metals found in sediment and biological tissues, together with the biochemical responses of S. herzbergii in the study areas, indicate that this species is still tolerant to adverse environmental conditions, but the presence of metals is a risk to the health of fish, mainly to fish from São Marcos, especially if chronically exposed.

Heavy metal contamination in a highly consumed Brazilian fish: immunohistochemical and histopathological assessments

Due to industrial, rural, and domestic waste disposal, heavy metals such as cadmium (Cd), chromium (Cr), lead (Pb), zinc (Zn), copper (Cu), and iron (Fe) continually infiltrate aquatic environments. These pollutants do not degrade naturally and, thus, have a high capacity for bioaccumulation in tissues and organs. The present study uses histological and immunohistochemical analyses to evaluate the contamination status of Salminus franciscanus, a large and economically important fish. Levels of Cd, Cr, Pb, Zn, Cu, and Fe were evaluated by atomic absorption spectrometry in the liver and muscle of fish sampled from two tributaries of the upper São Francisco River Basin, Brazil: the Abaeté and Paraopeba Rivers. In addition, histopathological alterations and expressions of three environmental biomarkers were assessed: metallothionein (MT), heat shock protein-70 (HSP70), and cytochrome P450-1A (CYP1A). The results show that fish from the Paraopeba River are unsuitable for human consumption, with several metals being detected above the safe limits established by the World Health Organization. Histopathological alterations in the liver and spleen were also significantly more frequent in fish from the Paraopeba River than in those from the Abaeté River (P < 0.05). Significant differences in the expressions of environmental biomarkers were observed between the rivers. Fish from the Abaeté River presented significantly higher values of the gonadosomatic index (GSI) and lower levels of metal contamination in the liver and muscle.

Heavy Metals and PAHs in Meat, Milk, and Seafood From Augusta Area (Southern Italy): Contamination Levels, Dietary Intake, and Human Exposure Assessment

Heavy metals and PAHs were measured in animal foodstuffs from Augusta-Melilli-Priolo area in order to evaluate the potential human health risk associated to their consumption. All heavy metals were detected in seafood products while most of them were 1 for baby, children and teenagers, indicating a non-carcinogenic risk for these age categories by seafood ingestion. The CRAs overcame 1*10-5 for almost age categories (except "baby") and for elderly, by seafood and beef ingestions respectively. Moreover, the MOE for PAHs showed a certain cancer risk for "baby" related to cow milk ingestion.

Rare earth element bioaccumulation in the yellow and silver European eel (Anguilla anguilla): A case study in the Loire estuary (France)

In the present work, rare earth elements (REEs) were measured in European eel muscles (Anguilla anguilla) from the Loire estuary in France. This study site is characterized by a large anthropogenic pressure with potential activities releasing REEs such as oil refineries, aeronautic and naval industries, wind turbine industries, hospitals with magnetic resonance imaging and coal-fired power plants. These activities may lead to increased REE concentrations in sediments the primary habitat of European eels. In the present work, REE bioaccumulation was evaluated by determining the concentrations in yellow and silver eel muscles sampled at three different locations in the Loire estuary and at two periods (2011/2012 and 2018/2019). The aims of this study were the understanding of the spatio-temporal influences (sampling site and sampling period) and intraspecific variations (age, sex, sexual maturation, length, weight, and parasitism) on the whole REE bioaccumulation. The mean value of the sum of REE concentrations (∑REEs) was 2.91, 6.48 and 12.60 µg/kg of muscle from respectively yellow eels, female silver eels and male silver eels fished in 2018/2019. The results showed that silver males accumulated more REEs than silver females and silver eels accumulate more REEs than yellow ones. Regarding the determination of spatio-temporal variations, an increase of REE concentrations for silver eel muscles between the two periods was observed, certainly related to the increase of REE uses. Finally, a trend of higher contamination of eels sampled in the downstream of Nantes was noticed for yellow eels.

Innovative health risk assessments of heavy metals based on bioaccessibility due to the consumption of traditional animal medicines

Few studies reported the extent of heavy metal accumulation in traditional Chinese medicines (TCMs). Currently, oral bioaccessibility of lead (Pb), cadmium (Cd), arsenic (As), mercury (Hg), and copper (Cu) present in traditional animal medicines was investigated with physiologically based extraction test-extracted in vitro model. We are the first to develop a health risk assessment strategy by combinational analysis of bioaccessible heavy metal levels to calculate target hazard quotient (THQ), target hazard index (THI) and cancer risk (CR), which has capacity to evaluate the heavy metal associated heath risk of traditional animal medicines. To precisely acquire a realistic risk assessment, questionnaire data was adopted to measure the frequency and duration of the exposure to traditional animal medicines, and the safety factor was highlighted as well. Our data revealed that the bioaccessibility of Hg was the lowest among the five heavy metals. After the adjustment with the bioaccessibility of each heavy metal to target hazard index (THI) values, excitingly, the results manifested that the consumption of traditional animal medicines might not exert an unacceptable health risk in a broad community. In addition, the CR values of As and Pb indicated that the risk of developing cancers was quite lower than their acceptable levels in the clinic.

Lead, Mercury and Cadmium in Fish and Shellfish from the Indian Ocean and Red Sea (African Countries): Public Health Challenges

The main aim of this review was to assess the incidence of Pb, Hg and Cd in seafood from African countries on the Indian and the Red Sea coasts and the level of their monitoring and control, where the direct consumption of seafood without quality control are frequently due to the poverty in many African countries. Some seafood from African Indian and the Red Sea coasts such as mollusks and fishes have presented Cd, Pb and Hg concentrations higher than permitted limit by FAOUN/EU regulations, indicating a possible threat to public health. Thus, the operationalization of the heavy metals (HM) monitoring and control is strongly recommended since these countries have laboratories with minimal conditions for HM analysis.

Source apportionment and seasonal variation in particulate PAHs levels at a coastal site in Belgium

In the present study, estimation of the atmospheric polycyclic aromatic hydrocarbons (PAHs) was done in particulate samples collected from De Haan, Belgium, during different seasons. The sampling site was situated very close to the north sea and far from the influence of local or industrial activities. The levels of PAHs depicted a distinct seasonal trend, being highest during the spring season. The observations of the study indicated a mean value of 2.6 ng m^-3 for concentration of all the 16 US EPA PAHs, thus being significantly lower when compared to results of previous studies focused on other sites. The dominating PAHs species reported were naphthalene, fluoranthene, benzo[a]anthracene, chrysene, and indeno[1,2,3c,d] pyrene. Assessment of the seasonal variation of the PAH levels was also done with respect to diagnostic ratio-based source identification, analysis of back trajectories, and principle component analysis. Burning of fossil fuels was observed to be the prominent source of atmospheric PAHs in the study area. Further, lifetime cancer risk assessment was performed to assess the detrimental health impacts on humans on being exposed to atmospheric PAHs. Particulate PAHs present in the ambient air of Belgium shows no carcinogenic health impacts. However, considering the industrial expansion in the region, efforts are required to prevent the environmental contamination of PAHs. Graphical abstract.

Trace elements and oxidative stress in the Ark shell Arca noae from a Mediterranean coastal lagoon (Bizerte lagoon, Tunisia): are there health risks associated with their consumption?

The current study examined the concentrations of ten trace elements (TE) (nickel, chromium, cadmium, iron, zinc, manganese, aluminum, copper, selenium and lead) in the edible tissue of the Ark shell Arca noae (L. 1758) from a Mediterranean coastal lagoon, the Bizerte lagoon during 2013-2014. The analysis of several redox status biomarkers, metallothioneins (MTs), malondialdehyde (MDA), glutathione peroxidase (GPx), reduced glutathione (GSH) and acetylcholinesterase (AChE), was monitored as a response to TE bioaccumulation and environmental parameters variability. Significant differences (p < 0.05) were observed between mean seasonal TE concentrations in A. noae soft tissue. The highest TE concentrations in A. noae soft tissues were recorded during summer, which coincided with the increase of body dry weight (BDW) and the gonad index (GI). During this season, biomarker responses were enhanced, revealing significant increases of MTs, MDA and GSH levels as well as GPx activity in A. noae tissues, while a decrease of AChE activity was observed. The levels of TE analyzed in A. noae and several parameters used to assess the potential human risk (estimated weekly intake, target hazard quotient and target hazard risk) were lower than the permissible limits for safe seafood consumption. Consequently, this shellfish can be considered safe for human consumption. This preliminary study presents prospects for the valorization of this seafood product in Tunisia's food sector. It also gives basal information for future environmental assessment studies in which A. noae could be used as early warning tools in the field of biomonitoring programs and confirms the usefulness of biomarkers to monitor the health status of aquatic organisms.

Assessment of metal mobility in sediment, commercial fish accumulation and impact on human health risk in a large shallow plateau lake in southwest of China

Sediment heavy metal pollution in the Dianchi Lake has been a long-term environmental problem of concern. This study investigated the lake sediment heavy metal contamination level, mobility, commercial fish metal accumulation and its impact on human health. The results show high As, Hg and Cd concentration in the sediment, while Pb and Cr contamination are insignificant. Sediment sequential extraction analysis shows that Hg in sediment has the highest portion of mobile fraction, followed by As, while the portion of mobile fractions of Cd, Pb and Cr in sediment is very low. The high concentrations of Hg and As in surface water and porewater were consistent with the chemical fraction composition of the two elements in sediment. Three major commercial fish species, Culterichthys erythropterus, Carassius auratus and Hypophthalmichthys molitrix, were collected for analysis of metal concentrations in their muscles. Among the same size of fish, C. auratus has the highest As concentration due to its bottom habitat and omnivorous feeding habits. On the other hand, C. erythropterus has the highest Hg concentration due to its relatively high trophic level position. The average THQ value of metals in fish tissue decrease in the order of As > Hg > Pb > Cd > Cr and the total THQ of average metal concentration in fish species decreased in the order of C. auratus > C. erythropterus > H. molitrix. Both THQ and total THQ is below 1, suggested no non-carcinogenic human health risk of fish consumption. However, TR of As in C. auratus was above 1.00E-04 threshold value, indicated potential carcinogenic human health risk. The results from this study indicate that although moderately to heavily contamination of Hg, As, and Cd occurred in Dianchi Lake sediment, only Hg and As tend to transport to surface water and accumulate in commercial fish due to their higher mobility in sediment.

Toxic Metal Implications on Agricultural Soils, Plants, Animals, Aquatic life and Human Health

The problem of environmental pollution is a global concern as it affects the entire ecosystem. There is a cyclic revolution of pollutants from industrial waste or anthropogenic sources into the environment, farmlands, plants, livestock and subsequently humans through the food chain. Most of the toxic metal cases in Africa and other developing nations are a result of industrialization coupled with poor effluent disposal and management. Due to widespread mining activities in South Africa, pollution is a common site with devastating consequences on the health of animals and humans likewise. In recent years, talks on toxic metal pollution had taken center stage in most scientific symposiums as a serious health concern. Very high levels of toxic metals have been reported in most parts of South African soils, plants, animals and water bodies due to pollution. Toxic metals such as Zinc (Zn), Lead (Pb), Aluminium (Al), Cadmium (Cd), Nickel (Ni), Iron (Fe), Manganese (Mn) and Arsenic (As) are major mining effluents from tailings which contaminate both the surface and underground water, soil and food, thus affecting biological function, endocrine systems and growth. Environmental toxicity in livestock is traceable to pesticides, agrochemicals and toxic metals. In this review, concerted efforts were made to condense the information contained in literature regarding toxic metal pollution and its implications in soil, water, plants, animals, marine life and human health.

Methylmercury and inorganic mercury in Chinese commercial rice: Implications for overestimated human exposure and health risk

China is the largest rice producer and consumer in the world, and mercury (Hg) levels, particularly methylmercury (MeHg), in rice and health exposure risks are public concerns. Total Hg (THg) and MeHg levels in 767 (domestic = 709 and abroad = 58) Chinese commercial rice were investigated to evaluate Hg pollution level, dietary exposures and risks of IHg and MeHg. The mean rice THg and MeHg levels were 3.97 ± 2.33 μg/kg and 1.37 ± 1.18 μg/kg, respectively. The highest daily intake of MeHg and IHg were obtained in younger groups, accounted for 6% of the reference dose-0.1 μg/kg bw/day for MeHg, 0.3% of the provisional tolerance week intake-0.571 μg/kg bw/day for IHg. Residents in Central China and Southern China meet the highest rice Hg exposure, which were more than 7 times of those in Northwest China. Lower concentrations than earlier studies were observed along the implementations of strict policies since 2007. This may indicate that a declining temporal trend of Hg in Chinese grown rice and associated exposures could be obtained with the implementations of strict policies. Though there exist Hg pollution in commercial rice, Hg levels in Chinese commercial rice is generally safe compared with Hg polluted sites. Populations dwelling in China have relatively a quite low and safe MeHg and IHg exposure via the intake of commercial rice. Strict policies contributed to the decrease in THg and MeHg levels in Chinese-grown rice. More attention should be paid to younger groups.

Mercury accumulation in fish species along the Portuguese coast: Are there potential risks to human health?

This paper aimed at evaluating the total mercury content in five common fish species from the western European Atlantic coastal waters, and the associated risk of consumption. Mercury concentrations in muscle of Atlantic mackerel (Scomber scombrus), Atlantic chub mackerel (Scomber colias), European anchovy (Engraulis encrasicolus), Atlantic horse mackerel (Trachurus trachurus) and European pilchard (Sardina pilchardus) ranged from 0.003 to 0.20 mg kg^-1 wet weight, and no significant differences were observed between the average concentration in each species. A significant increasing trend in mercury content with fish size was observed for all species (except for European anchovy), suggesting mercury bioaccumulation throughout their life cycle. Still, the mercury content was far below the European Food Safety Authority and World Health Organization food safety thresholds in all species, highlighting the low risk to human health due to the ingestion of these species and the importance of consumer options for risk reduction.

Anthropo-niche characterization of Mediterranean cephalopods with trace elements and isotopic niches

Human pressure leaves a mark on coastal ecosystems that can be used to study the ecology of marine species. This study compared the trace elements (TEs) composition and isotopic niche metrics of the squid Loligo vulgaris, the cuttlefish Sepia officinalis and the octopus Octopus vulgaris in the western Mediterranean Sea. The results revealed that anthropogenic pressure clearly affected coastal waters and the habitat use of these three cephalopods. Anthropogenic pressure in coastal areas, measured by the LUSI index, correlated with the TEs composition of cephalopods. The DistLM analysis showed that Cr and Zn were strong predictor variables of the LUSI matrix on all three cephalopod species. In this study, isotopic niche, combined with the CAP analysis of TEs, were plotted in a bivariate manner, which could refer to an "anthropo-niche". We provide a useful heuristic scheme for analyzing the interplay among coastal influence, trophic level, and the TEs from environment.

Critical review of mercury contamination in Sri Lankan fish and aquatic products

Mercury (Hg) in fish and aquatic products is a potential threat to human health and international trade, and guidelines of international advisory bodies are established for assessing Hg in these foods. As fish are the most consumed animal protein in Sri Lanka, this assessment summarises for the first-time total mercury concentrations in Sri Lankan marine and freshwater fish, invertebrates, aquatic plants, and fisheries products. It reveals that Hg levels in fish and other edible aquatic species are mostly below the published safety limits, except for certain top trophic level fish (swordfish, tuna, marlin). The review also highlights gaps in Sri Lankan Hg assessments such as a total lack of data for methyl‑mercury in these aquatic species and food products. This data compilation and assessment will serve as an initial baseline for comparison with results from future monitoring and research studies in Sri Lanka while adding to the world-wide Hg database.

Bioaccumulation of heavy metals in some commercially important fishes from a tropical river estuary suggests higher potential health risk in children than adults

The Karnaphuli River estuary, located in southeast coast of Bangladesh, is largely exposed to heavy metal contamination as it receives a huge amount of untreated industrial effluents from the Chottagram City. This study aimed to assess the concentrations of five heavy metals (As, Pb, Cd, Cr and Cu) and their bioaccumulation status in six commercially important fishes, and also to evaluate the potential human health risk for local consumers. The hierarchy of the measured concentration level (mg/kg) of the metals was as follows: Pb (13.88) > Cu (12.10) > As (4.89) > Cr (3.36) > Cd (0.39). The Fulton's condition factor denoted that fishes were in better 'condition' and most of the species were in positive allometric growth. The bioaccumulation factors (BAFs) of the contaminants observed in the species were in the following orders: Cu (1971.42) > As (1042.93) > Pb (913.66) > Cr (864.99) > Cd (252.03), and among the specimens, demersal fish, Apocryptes bato appeared to be the most bioaccumulative organism. Estimated daily intake (EDI), target hazard quotient (THQ), hazard index (HI) and carcinogenic risk (CR) assessed for potential human health risk implications suggest that the values were within the acceptable threshold for both adults and children. However, calculated CR values indicated that both age groups were not far from the risk, and HI values demonstrated that children were nearly 6 times more susceptible to non-carcinogenic and carcinogenic health effects than adults.

Cadmium and Lead Hazardous Impact Assessment of Pond Fish Species

The current study aims to assess the concentration of cadmium (Cd) and lead (Pb) in five tissues of Cirrhinus mrigala, Labeo rohita, and Catla catla collected from fishponds of Jamshoro and Larkana, Sindh, Pakistan. Meanwhile, the levels of Cd and Pb in feeding materials, water, and sediments of fishponds of both areas were also studied. The daily intake and hazardous impact assessment of Cd and Pb by muscles of three fish species of fishponds of both areas were estimated. The concentration of Cd in tissues of C. mrigala and C. catla of Larkana were higher than that in tissues of same fish species of Jamshoro whilst Pb contents in tissues of fishes of Jamshoro were high (p > 0.05). The feeding materials of fishponds of Larkana were enriched with Cd whilst Pb was high in feeding material of fishponds of Jamshoro. The estimated bioaccumulation factor, average daily intake, and hazardous quotient of Pb were high as compared to Cd in all studied fish species of fishponds of Larkana and Jamshoro. The hazardous quotient of Pb indicated that the local population of both areas might have a potential toxic risk. Graphical abstract ᅟ.

Bioaccumulation and heavy metal concentration in tissues of some commercial fishes from the Meghna River Estuary in Bangladesh and human health implications

Despite the beneficial aspect of aquatic food's consumption, bioaccumulation of toxic metals in fish can enhance the health risk for the consumers. Heavy metals were measured from editable tissues of some commercial fish species like Latis calcarifer, Silonia silondia, Clupisoma garua, Planiliza subviridis, Otolithoides pama, Tenulosa ilisa, Rhinomugil corsula, and Aila coila in the Meghna river estuary in Noakhali district. Heavy metals such as As, Pb, Cd, Cu, and Cr were detected by ICP-MS, which were significantly different (p ≤ 0.01), and the hierarchy of all mean concentrations were: Cu (5.14 mg/kg) > Pb (3.79 mg/kg) > As (1.08 mg/kg) > Cr (0.78 mg/kg) > Cd (0.12 mg/kg). The mean concentration of Cu (6.62 mg/kg) imparted to the maximum level in L. calcarifer, which slightly exceeded the Bangladesh food safety guideline. The mean BAFs of the contaminants were found as: Pb (1042.29) > Cr (1036.47) > As (934.84) > Cd (832.77) > Cu (772). Further, L. calcarifer, S. silondia, C. garua, and P. subviridis showed the bioaccumulative status. To assess the health risk effects, estimated daily intake (EDI), target hazard quotient (THQ) and carcinogenic risk (CR) were conducted. THQs for both adult and children consumers were <1, indicating that, consumers would not experience the non-carcinogenic health effects. Although children were more susceptible than adults, CR for all the consumers was found in the acceptable range (10^-6 to 10^-4).

Mineral Content of Various Portuguese Breads: Characterization, Dietary Intake, and Discriminant Analysis

The chemical composition and daily mineral intake (DMI) of six macro (calcium, magnesium, sodium, potassium, phosphorous, and chloride) and four microminerals (copper, iron, manganese, and zinc) were determined in four types of Portuguese breads (white wheat, maize, wheat/maize, and maize/rye breads). Samples were processed with microwave assisted digestion and mineral composition was determined with a high-resolution continuum-source atomic absorption spectrometer with flame and graphite furnace. Bread contributes to an equilibrated diet since it is rich in several minerals (0.21 mg/100 g of copper in wheat bread to 537 mg/100 g of sodium in maize/rye bread). Maize/rye bread presented the highest content of all minerals (except phosphorous and chloride), while the lowest levels were mainly found in wheat bread. Median sodium concentrations (422–537 mg/100 g) represented more than 28% of the recommended daily allowance, being in close range of the maximum Portuguese limit (550 mg/100 g). Maize/rye bread exhibited the highest DMI of manganese (181%), sodium (36%), magnesium (32%), copper (32%), zinc (24%), iron (22%), potassium (20%), and calcium (3.0%). A Principal Component Analysis (PCA) model based on the mineral content allowed the differentiation among white wheat, maize, and maize/rye bread. Zinc, magnesium, manganese, iron, phosphorus, potassium, copper, and calcium proved to be good chemical markers to differentiate bread compositions.

Organotropism of total mercury (THg) in Cichla pinima, ecological aspects and human consumption in fish from Amazon region, Brazil

Specimens of the Cichla pinima are of ecological and economic importance in the Amazon region and are a good bioindicator species of Hg bioaccumulation. Adult specimens of Cichla pinima were obtained by fisheries in the Tapajós river region's impacted gold mining area. Tissues such as muscle, liver, skin, and gill were submitted for total mercury (THg) analysis. For hepatic bioavailability, assays were carried out in the whole liver and in the sub-cellular hepatic fraction. The weight-length relationship showed an equation of W = 2E - 06L^3.3002 (R² = 0.856) indicating an allometric growth. The mean THg values found in the muscle tissue of 676 ± 258 μg kg^-1 were below the maximum limit established for human consumption, but were similar to Cichla fish from other areas impacted by Hg in the Amazon region. The trends of levels in the tissues were as follows: liver>muscle>gonads>skin>gill, with no significant differences between the gills and skin. A significant and positive correlation as r_s = 0.65 was obtained between the THg contents in cytosolic fraction and the total hepatic THg (liver homogenate). However, only 7% of the THg were found and were available to the sub-cellular hepatic fraction. This profile can be an indicative of a hepatic cellular transference in fish exposed to high Hg levels in the Amazon region now that low concentrations of Hg have been found in the sub-cellular fraction. However, data of differential THg partition in the subcellular compartments should be considered, since others' hepatic fractions can act in the Hg linkage into the cell.

Potentially toxic elements in commonly consumed fish species from the western Mediterranean Sea (Almería Bay): Bioaccumulation in liver and muscle tissues in relation to biometric parameters

Marine pollution is one of today's most relevant problems. Public awareness has been raised about the harmful potential of heavy metals (HMs) accumulating in edible fish and possibly ending up in human diet through the food chain. This study aimed to characterize and evaluate As, Cd, Cr, Cu, Ni and Pb contents in four edible fish species from the western Mediterranean Sea. Liver and muscle toxic elements were determined by GF-AAS in Mullus surmuletus, Merluccius merluccius, Auxis rochei and Scomber japonicus from Almería Bay (Spain). Muscular composition, biometrics and trophic levels were also determined. The mean PTE concentration levels (mg kg^-1, DW) in fish muscle tissue were: As (2.90-53.74), Cd (0.01-0.18), Cr (0.53-2.01), Cu (0.78-6.93), Ni (0.06-0.24), Pb (0.0-0.32). These concentrations did not exceed the maximum limits set by European legislation (Commission Regulation (EC) No. 1881/2006) for the intake of these marine species. Accumulation of toxic elements tends to be seen in the liver (As (7.31-26.77), Cd (0.11-8.59), Cr (0.21-2.94), Cu (2.64-16.90), Ni (0.16-1.03), Pb (0.0-0.99)). As was the element at highest risk in this Mediterranean region, especially due to red mullet values in muscle. The high As contents with living habits as benthic species that feed near the coast. HMs, especially muscle Cd contents, were associated with higher contents of lipids and organic matter, and bigger specimen size (length and weight), while As was linked to higher fish protein content. However, these relationships between potentially toxic elements (PTE) and biometric indices and body composition parameters depend on species. Finally, the THQ indices indicated that eating fish from Almería Bay poses no human health risk despite pollution from the Almería coastline.

Trace minerals in tilapia fillets: Status in the United States marketplace and selenium supplementation strategy for improving consumer's health

This goal of this study was to highlight the importance of minerals in the diet of fish for meeting micronutrient requirements in the human diet. First arsenic, calcium, cadmium, copper, iron, molybdenum, magnesium, manganese, sodium, phosphorus, potassium, selenium, and zinc concentrations of twelve commercially available tilapia samples were measured. The nutritional value of fillets in regard to their mineral content were assessed to establish potential health benefits or risks for consumers. The health benefit value of selenium was also calculated. Positive health benefit values indicate that tilapia fillets in the United States marketplace of this study do not pose health risks associated with mercury exposures. Selenium was the trace mineral of interest. After the market study, a seven-week fish feeding trial was conducted to study the influence of organic versus inorganic dietary selenium on Nile tilapia (Oreochromis niloticus). Fish were fed two different diets enriched with the same concentration (0.01g kg-1) of selenium in form of inorganic (sodium selenite) or organic (seleno-L-methionine) selenium in triplicate groups. There were no significant differences between growth and biometrics of fish fed different diets (p>0.05). At the end of trial twelve fish from each treatment were collected. Fillets of fish fed organic selenium had selenium concentrations of 0.55 ± 0.01 μg g-1 which were significantly (p<0.05) higher than fish fed inorganic selenium at levels of 0.22 ± 0.008 μg g-1 or fish samples from the marketplace with a selenium level of 0.2 ± 0.03 μg g-1. Fish fed organic selenium also had significantly higher (p<0.05) plasma and kidney selenium in comparison to fish fed inorganic selenium. No significant differences (p>0.05) were observed in glutathione peroxidase activities in either the plasma or liver of Nile tilapia in the different treatment groups. This study shows that organic selenium is a better option for production of Nile tilapia fillets rich in selenium.

Toxicity Assessment of Impacted Sediments from Southeast Coast of Tunisia Using a Biomarker Approach with the Polychaete Hediste diversicolor

Toxicity caused by exposure to pollutants from marine sediments is a consequence of the interaction between biota and xenobiotics most frequently released by anthropogenic activities. The present work intended to characterize the toxicity of natural sediments putatively impacted by distinct human activities, collected at several sites located in the south of the Gulf of Gabes, Zarzis area, Tunisia. The selected toxicity criteria were analysed following ecologically relevant test conditions. Organisms of the polychaete species Hediste diversicolor were chronically exposed (28 days) to the mentioned sediments. Toxicity endpoints were biomarkers involved in the toxic response to common anthropogenic chemicals, namely neurotoxic (acetylcholinesterase), anti-oxidant (catalase, glutathione peroxidase), metabolic (glutathione S-transferases) enzymatic activities, and oxidative damage (lipid peroxidation, TBARS assay). The chemical characterization of sediments showed that the samples collected from the site near an aquaculture facility were highly contaminated by heavy metals (Cd, Cu, Cr, Hg, Pb, and Zn) and polycyclic aromatic hydrocarbons (fluorene, phenanthrene, anthracene, fluoranthene and pyrene). H. diversicolor individuals exposed to the sediments from this specific site showed the highest values among all tested biomarkers, suggesting that these organisms were possibly under a pro-oxidative stress condition potentially promoted by anthropogenic pollution. Moreover, it was possible to conclude that individuals of the polychaete species H. diversicolor responded to the chronic exposure to potentially contaminated sediments from the southeast coast of Tunisia, eliciting adaptive responses of significant biological meaning.

Trace element concentrations, ecological and health risk assessment in sediment and marine fish Otolithes ruber in Oman Sea, Iran

This study aimed to investigate the concentration of Cd, Ni, Cr, Pb and As in the tissues of Otolithes ruber and surface sediments in the Oman Sea. Trace element concentrations were analyzed by flame atomic absorption spectrophotometer (FAAS) for ecological and health risk assessment. The results showed a significant difference in trace element concentrations of the liver, muscle and sediments between different stations (p < 0.05). Potential ecological risk index (PER) indicated very high risk for Cd at all stations. Estimated daily intake (EDI) for consumption of Otolithes ruber for Cr, Pb and As was lower than tolerable daily intake (TDI). The mean target hazard quotient (THQ) of Cd and Ni were higher than 1 at all stations. Target cancer risk (TR) for Ni and As were higher than the acceptable value range at all stations. Accordingly, the risk of cancer due to the long-term consumption of this fish can be concerned.

Selenium, total mercury and methylmercury in sardine: Study of molar ratio and protective effect on the diet

The purpose of this work was to evaluate the risk-benefit associated with canned sardine consumption, considering the selenium, the mercury and the methylmercury contents and the Se:Hg molar ratio and the Se-health benefit value (HBV) index. In this study, 63 canned sardine samples were purchased worldwide and for the determination of selenium and mercury species, the inductively coupled plasma optical emission spectrometry and thermal decomposition and amalgamation atomic absorption spectrometry were employed. The mean results obtained for the Brazilian samples varied between 12.6 and 65.5 μg kg^-1 for Hg; <3.7 and 45.4 μg kg^-1 for methylmercury; 310 and 1370 μg kg^-1 for Se. The MeHg/Hg ratio showed that the most toxic forms of Hg (MeHg) is predominant in 52 and 39% of the Brazilian samples conserved in tomato sauce and in oil, respectively. Nevertheless, the Se-HBV index and the Hg:Se and Se:Hg molar ratios indicated that the selenium content in canned sardine samples is enough to provide a protective effect on the Hg species.

Probabilistic Integrated Human Mixture Risk Assessment of Multiple Metals Through Seafood Consumption

Inorganic arsenic (iAs), cadmium (Cd), lead (Pb), and methylmercury (MeHg) are toxic metals that cause substantial health concern and are present in various seafood items. This study linked probabilistic risk assessment to the interactive hazard index (HI_INT ) approach to assess the human mixture risk posed by the dietary intake of iAs, Cd, Pb, and MeHg from seafood for different age populations, and joint toxic actions and toxic interactions among metals were also considered in the assessment. We found that, in combination, an iAs-Cd-Pb-MeHg mixture synergistically causes neurological toxicity. Furthermore, an iAs-Cd-Pb mixture antagonistically causes renal and hematological effects and additively causes cardiovascular effect. Our results demonstrated that if toxic interactions are not considered, the health risk may be overestimated or underestimated. The 50th percentile HI_INT estimates in all age populations for neurological, renal, cardiovascular, and hematological effects were lower than 1; however, the 97.5th percentile HI_INT estimates might exceed 1. In particular, toddlers and preschoolers had the highest neurological risk, with 0.16 and 0.19 probabilities, respectively, of neurological HI_INT exceeding 1. Saltwater fish consumption was the principal contributor to the health risk. We suggest that regular monitoring of metal levels in seafood, more precise dietary surveys, further toxicological data, and risk-benefit analysis of seafood consumption are warranted to improve the accuracy of human mixture risk assessment and determine optimal consumption.

Heavy metals concentrations in some commercially key species from Sicilian coasts (Mediterranean Sea): Potential human health risk estimation

Trace elements were measured in the edible tissues of target marine species (Sardina pilchardus, Mullus barbatus, Mullus surmuletus, Merluccius merluccius and Parapenaeus longirostris) collected in some of the main ports of the Sicilian coast (southern Italy) in order to evaluate the potential human health risk associated to their consumption. Cadmium, Pb and Hg were below the tolerable limits reported by the European Union in foodstuffs (Commission Regulation (EC) 1881/2006) except for Hg in P. longirostris from one sampling site. The health risk for consumers was assessed both for adults and children calculating the estimated weekly intake (EWI), the target hazard quotient (THQ) and the lifetime cancer risk (CR) for each element. The EWI did not exceed the provisional tolerable weekly intake (PTWI) recommended by the European Food Safety Authority and THQs were < 1 in most cases. Further, the probabilistic distributions of health hazard were evaluated through Monte-Carlo simulation which confirmed a non-carcinogenic risk. With some exceptions related to As exposure, the results obtained definitively confirm the goodness of the fishery commercial resources in one of the most important seafood market of the central Mediterranean Sea and represent a positive data for the assessment of the good environmental status for descriptor 9 of the Marine Strategy Framework Directive in this area of the basin.

Proximate, fatty acids and metals in edible marine bivalves from Italian market: Beneficial and risk for consumers health

Seafood is recognized as a healthy food choice due to high contents of essential nutrients, including polyunsaturated fatty acids (PUFAs) of the n-3 family. However, seafood is often contaminated by toxic compounds, which have adverse effects on human health. The aim of this study was to provide information about the percentage of edible part, condition index and the benefit and risk for human consumers health associated to the consumption of eight bivalve species (Flexopecten glaber, Mimachlamys varia, Modiolus barbatus, Mytilus galloprovincialis, Ostrea edulis, Ruditapes philippinarum, Solen marginatus and Venus verrucosa) of high commercial value, purchased from Taranto local fish markets. High percentage of edibility and condition index were found in all analysed species. The relatively high protein content, low levels of lipid and high percentage of healthy n-3 PUFAs make M. varia, O. edulis, S. marginatus, M. galloprovincialis, M. barbatus more suitable for benefit to consumers. Provisional tolerable weekly intake and hazard index calculated on the basis of trace metals in edible tissues, indicated specific recommendations for a responsible daily consumption of shellfish. For the most part of studied species, the estimated balance between beneficial and risk for consumers recommend a daily portion (RDP) lesser of 60 g/person/day than M. galloprovincialis, O. edulis and R. philippinarum (≥60 g/person/day). Careful risk-benefit considerations should promote seafood consumption while minimizing exposure to toxic contaminants.

Systematic review of arsenic in fresh seafood from the Mediterranean Sea and European Atlantic coasts: A health risk assessment

Arsenic in the environment pose major threats to human health, and especially the inorganic form can result in adverse health effects. This review analyse papers from 2004 to 2017 on As in fresh fish and molluscs caught in the Mediterranean sea and the European coast of the Atlantic ocean allowing the identification of the marine area with a greater As bioavailability and in particular the identification of the European populations more exposed to In-As by consuming fresh seafood. Results were separated on the base of the fishing site and the concentrations were reworked to assess the average daily intake to In-As as well as Target Hazard Quotient and Cancer Risk. Overall, the greater availability in Tot-As concentration in the pelagic compartment found in the Mediterranean Sea is not present along the European coasts of Atlantic Ocean. Furthermore, only in the Mediterranean Sea, results highlighted significant differences between Tot-As concentrations in seafood subgroups. In both areas, In-As concentrations showed the following trend: molluscs > pelagic > demersal with significant differences between subgroups. The European populations more exposed to In-As from fish and molluscs are the French, Spanish, Italian and Greek, with particular regards to children of 3-6 years old, which should minimize the consumption of molluscs to avoid carcinogenic and non-carcinogenic risks.

Cadmium, lead and mercury in muscle tissue of gilthead seabream and seabass: Risk evaluation for consumers

Cadmium (Cd), lead (Pb) and mercury (Hg) presence was investigated in the muscle tissue of gilthead seabream and seabass, collected from various aquaculture sites of the Aegean and Cretan Sea as well as from the fish market (fisheries). Risk for the Greek population through consumption of these species was estimated using two approaches: Target Hazard Quotient (THQ) and Hazard Index (HI). All heavy metal levels in the fish tissue were below the established safe limits for consumption. Metal accumulation was found to differ amongst mode of production, species, location and seasonality. Seabass demonstrated higher Hg and lower Cd concentrations than seabream, Hg and Pb seem to be more accumulated in closed seas and Pb values displayed a linear increasing trend from warmer to colder periods. Regression analysis revealed that the main contributing factor to Cd accumulation is species (beta: -0.28, 95%CI: -0.48 to -0.09); lead is predominately affected by seasonality (beta: 0.44, 95%CI: 0.29 to 0.59), Hg accumulation is mainly affected by location (beta: -0.32, 95%CI: -0.61 to -0.03) while wild seabream accumulates greater levels for Hg and Pb than farmed. Risk analysis demonstrated that consumption of the studied species, is safe for all metals (HI < 0.460 and TTHQ < 0.299).

Metals and elements in sardine and anchovy: Species specific differences and correlations with proximate composition and size

Species - specific differences in the levels of 26 metals and elements in sardine and anchovy are investigated and the factors of proximate composition (proteins, lipids, ash) and body size (length, weight) that may affect the metal and elemental concentrations in fish are explored. Statistical analysis revealed that levels of metals and elements in fish seem to strongly depend on species. Significantly higher levels of most of the metals and elements studied have been observed in anchovy compared to sardine at each of six different sites. The observed species-specific differences in metal content could be attributed to different proximate composition and size among other factors. The significant (positive or negative) correlations found between lipids, proteins, ash, weight, length and metals or elements, suggest that higher levels of most of the metals and elements studied can be associated with lower lipid content, greater protein and ash content and smaller size.